It took decades for Congress to address the problem. When, at long last, federal legislation was passed, some people raised constitutional objections, but few took them seriously. The objections required the Supreme Court to adopt unheard-of constitutional theories, hamstringing well-established powers on the basis of hysterical fears about a tyrannical federal government. Even the law’s opponents were surprised when the Court took those objections very seriously. Some warned that the Court was overreaching, and that its intervention would seriously hurt large numbers of innocent people, but the Court thought it was more important to rein in Congress.

You might assume I’m talking about health care reform. I’m not. I’m talking about child labor—and a 1918 decision by the Supreme Court that history has not looked kindly upon.